Process of drawing, forging, or swaging hollow metal articles.



W. SCRIMGEOUR.

PROCESS OF DRAWING, FORGING, 0R SWAGING HOLLOW METAL ARTICLES.

APPLICATION FILED MAR. 22. 1915.

1 l 5 l ,222. Patented Aug. 24, 1915.

Fail

l(I l ll!llllllll Il l l4 WILLIAM SGRIMGEOUR, OF PORTSMOUTH, VIRGINIA.

PROCESS OF DRAWING, FORGING, 0R SWAGING HOLLOW METAL ARTICLES.

Specification of Letters Patent.

v Patented Aug. 24%, 1915.

Application filed March 22, 1915. Serial No. 16,180.

To all whom it may concern:

Be it known that I, WILLIAM Sonmecoun, a. citizen of the United States, residingat Portsmouth, in the county of Norfolk and State of Virginia, have invented certain new and useful Improvements in Processes of Drawing, Forging, or Swaging Hollow Metal Articles, of which the following is a specification.

My invention relates to a process of drawing, forging or swaging hollow metal articles, such as the casings for projectiles.

In making articles of this character it is desirable that the operation of drawing, forging or swaging shall be so conducted as to leave the blank of a shape approximating as closely as may be, the nal shape of the completed article, in order that there may be little finishing work required, and that no metal need be unnecessarily removed.

In order to attain this result, I so shape the blank that additional metal is provided at those places at which, in the operation of forging, swaging or drawing, the metal would tend to be withdrawn or displaced.

The invention will be readily understood from the accompanying specification and drawings, in which- 4 Figure 1 shows various steps in the formation of a hollow article, such as a shrapnel casing; Fig. 2 is a diagrammatic representation of the portions of the ms in which the block of metal is formei into the first blank; Fig. 3 is like Fig. 2, b, t showing the press during the operation of completing the hollow article; Fig. 4 is a section of the lower end of a partly formed article; and Fig. 5 is a section of the lower portion of the completed article. a

suitable mechanism may be used for carrylng out the process, but I prefer to use that' shown in my copending application Serial No. 7,817, filed February 12, 1915.

In carrying out the process, a block of metal, suchfisteel or 113011, is heated to a suitable temperature and, then placed in the cavity of thedieblock A. Thereupon the tool 11 is forced down into the block to form an inner cavity corresponding to the shape of the tool 11. During this 0 eration the tool 17 is held up by the toggle evers 51, 52, and as the upper surface of the tool 17 is rounded or convexed, a. corresponding depression is made in the bottom of the shaped end 0 The operating rod 53 which may be actuated by any suitable mechanism then causes the lowering of the tool 17 (as shown in F g. 3) whereu on another swaging or drawm tool 12 is orced downward into the blank thereby drawing it downwardly through the cylindrical openin at the lower the die, thus forming a hollow article of the shape G. During this operation, metal at the periphery g of the bottom of the blank is bent or flows around the lower edge of the tool 12, so that a substantially flat bottom, of uniform thickness, and at right angles to the axis of the tool, is

formed. There is a tendency for the metal to flow around the lower edges of a drawing tool, such as 12, as it is pressed downward,

with the resultant formation of a rounded bottom on the article. being formed" or shaped. Where the article is designed to have a flat bottom, it has heretofore been necessary to furnish additional metal, as shown in dotted lines in Fig. 5, to ermit of the surplus being removed, there y necessitating an additional operation and wasting metal. By the use of my process, these additional operations are lar ely avoideda as very little if any metal nee s to be removed to square up the bottom of the article, and the quantity of metal to be removed is, in any event, reduced to a minimum.

While I have described the invention as applied'to the formation of an article having a particular shape, the invention is obviously applicable to articles having a great variety of both interior and'exterior contours; and while only two swaging or drawing steps have been described, obviously, there may be used additional intermediate steps to bring the article into the final form desired. In practice, I have found that a cylindrical casing, such as that of a shrapnel shell, may be successfully formed at one heat, by the two operations above described, and with a flat bottom surface of substantially uniform thickness and at right angles to the axis of the casing.

What I claim is The process of drawing, swaging or forging hollow cylindrical metal articles so that ice the bottom surface shall be at right angles to I the axis, which consists in making a blank In bestimon whereof I aflix my signature having a gottom .vflith larger quantities 01; in presence 0 two witnesses. meta at rt-e p erip ery t an in t e centra portion and concaved on its outer surface, WILLIAM Q R' 5 and then forcing the blank through a cy- 'Witnesses:

lindrical die-opening, thereby drawing the C. G. Enema, excess of inetal into the walls of the shell. HELEN BEAR. 

